1. Field of the Invention
The present invention relates to a ratchet wrench, and more particularly to a ratchet wrench having an additional driving device.
2. Description of the Prior Art
Various kinds of ratchet wrenches have been developed for effectively driving the fasteners. U.S. Pat. No. 5,058,463 to Wannop discloses a typical ratchet wrench having a driving device rotatably received in a driving head, and a device provided for rotating the driving device with bevel gears. However, the bevel gears are subjected with large torques or large forces whenever the ratchet wrench is used such that the bevel gears will be easily damaged.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional ratchet wrenches.